Sand filter.



PATENTED JULY 7, 1903.

N0 MODEL Patented July 7, 1903.

PATENT OEEIcE.

GODFREY ENGEL, OF BALTIMORE, MARYLAND.

SAND FILTER.

sPEc IE-IcA'rIoN forming part of Letters Patent No. 733,174., dated July 7, 1903.

Application filed August 27, 1902. Serial No. 121,206. (No model.) i

To (LZZ whom it may concern.-

Be it known that I, GODFREY ENGEL, a citizen of the United States, and a resident of the city of Baltimore, State of Maryland, have invented certain Improvements in Sand Filters, of which the following is a specification.

My invention relates to certain improvements in filters; and it consists more particularly in an improved sand filter for use in connection with the treatment of sugar solutions.

The object of the invention is to provide a device which while being of relatively simple construction shall effectually and efficiently perform its functions, the construction, moreover, being such that the filtering medium can be cleansed after use without the necessity for its removal from the filter-casin These objects I attain as hereinafter set forth, reference being had to the accompanying drawings, in which Figure 1 is a side elevationof my improved filter. Fig. 2 is a sectional elevation of the filter, showing the relative arrangement of its various parts. Fig. 3 is a sectional plan view on the line 3 3, Fig. 2; and Figs. 4, 5, and 6 are sectional elevations showing the detail construction of the joints between the filter-screens and the parts of the casing with which they contact.

In the above drawings, A is a substantially cylindrical casing, formed in the present instance of a sheet-metal section a, to which is riveted a cast top section a and a substantially conical cast bottom section a this latter having an inlet-opening a a dischargeopening a and an opening or, provided with a valve a, through which the filtering medium may be removed. Each of the openings a and a is preferably flanged for the attachment of suitable pipes, and it will be seen that the valve a is pivotally supported, there being a lever (1, pivoted to the casing A at a and having a threaded bolt a pivotally attached to one of its ends whereby the valve may be locked or retained inits closed position. The upper section a of the casing Ais provided with projecting lugs a whereby it may be hung or carried by any suitable support, and the top edge of said section is flanged and recessed, as shown in Fig. 4, there being in said recess any desired form of packing a A cover B is constructed to fit over and close the top of the casing A, its flanged edge I) engaging with the packing a and the whole cover being retained in position by means of bolts b, which are pivotally carried by lugs a on the casing aand are provided with nuts b having projections or handles whereby they may be turned. There is an annular recess in the under side of the cover B containing packing b whereby a tight joint is made between said cover and the upper end of a corrugated and perforated cylindrical screen 0, whose lower end has riveted to it a conical section 0, which in turn is supported upon a packing-ring 0, held in a recess in the lower section a of the casing A. The corrugated screen 0 is reinforced by a number of,

annular bands 0', placed as shown in Fig. 2, the object of these being to aid in preserving the form of the screen by making its distortion when acted upon by the internal pressure practically impossible. The corrugations increase the resisting power of the structure to longitudinal compression when the cover is made to bear strongly upon the same in order to make tight joints between the screen and the packing, the bands being advisable in order to strengthen what would otherwise be a relatively weak device.

The portion of the casing A having the flanged opening a" is provided with an inwardly-extending tubular portion'd, whose inner end is expanded into a conical flanged mouthpiece d,the uppersurfaceofthe flanged portion being recessed and having a packingring (1 therein, in addition to which there is a lug or projection d preferably formed integral with the conical section cl. Asecond cylindricalscreen I) bears upon the packingring d and is supported by the inwardly-projecting tubular section d concentrically with the screen 0, there being also a cover D to the screen D, which is held in position by a bolt (1 extending through the screen D and entering a suitable opening in the lug d The upper'end of the bolt 61 is threaded and there is a nut or hand-wheel 01 upon it, whereby the cover 01 and consequently the screen D are held in position, it being understood that a tight joint between the cover and the said screen is secured by means of a packing-ring d inthe same manner as shown in Fig. 6.

move any baterioloriotl or (that In operation the space between the two screens 0 and D is filled with particles of sharp sand or ground silica of such size that they will not pass through the perforations in said screens, and the solution to be purified or filtered is allowed to enter the casing through the opening a Rising between the casing A and the casing 0 this liquid passes through the said screen and the sand E,finally passing through the screen D and flowing out to the discharge-opening a When it is desired to clean the filter to reing material may be discharged, substaiv tially as described.

3. The combination in a filter, of a casing, with two substantially cylindrical screens Within the same, one of said screens being cor rugated longitudinally and having strength ening-bands around it in engagement with said corrugations, the casing being provided with openings for the admission and discharge of liquid to be filtered, substantially as de-V scribed.

4. The combination in a filter, of a casing r yr 1 mvr qqivqa rqquqr Q0 nt 

